[Case of a large intra and extra medullary abscess of the spinal cord due to dermal sinus].

Congenital dermal sinuses, resulting from abnormal neurulation, are relatively uncommon and cause the patients to contract intraspinal infection. Sometimes, this intraspinal infection develops intramedurally abscess with severe neurological deficits. Therefore, a lack of awareness about this problem can result in fatal neurological sequelae. We report the case of a 1-year-old boy who had a lumbo-sacral dimple at birth without further evaluation. He presented repeated fever and rapidly progressive paraplegia. MRI showed a huge intraspinal and intramedullary abscess with dermoid, which was thought to be the result of a dermal sinus. Subsequently, he was transferred to our hospital and received immediate surgery. The patient underwent irrigation of purulent material in the intraspinal abscess including on intramedullary lesion, removal of dermoid tumor, and the resection of the dermal sinus. After that, he was treated with 8 weeks of antibiotic therapy. The patient remained paraplegia but made improvement. This patient illustrates the importance of the recognition and evaluation of skin markers. Prophylactic surgery is indicated to prevent dangerous and recurrent infections of the central nervous system.